The present application relates generally to the field of occupant classification systems for vehicle seating. Vehicle seats may include occupant classification systems to attempt to determine if the seat is occupied by an adult, a child, or no one. Vehicle seats may also include other auxiliary components such as seat heaters, empty seat detectors, and serialization components. Current occupant classification systems use the seat bottom heater to determine occupant classification, which helps in determining whether a protective device (e.g., an airbag) will deploy or not during a crash event. A control algorithm divides the data from the seat bottom heater into two regions to determine occupant classification; the first region indicating that the status is empty or small and the second region indicating that the status is either large or occupied.
Similar to the seat bottom heater, the seat back heater also has two regions. The seat back heater is used for object presence classification or seat belt reminder (SBR). Measurements located within the first region indicate that the seat belt reminder will be disabled (i.e. OFF) and measurements in the second region indicate that the seat belt reminder is enabled (i.e. ON).
The seat back heater algorithm also requires input from the occupancy classification status to help with the seat belt reminder status. In the event that the occupancy classification status is empty or small and the object presence classification is enabled the occupancy classification status overrides the object presence classification and disables (i.e. OFF) the seat belt reminder. This situation only occurs when the occupancy classification is empty/small or unoccupied otherwise the object presence classification reports its actual classification.
Using this method for determining occupant classification and seat belt reminder status works for all occupants and seat positions however it does not mitigate well enough for electronic devices. Therefore there are instances where an electronic device will cause a misclassification for occupant classification, such as by enabling the airbag without an occupant sitting in the seat.